Paradoxically, since smoking also protects against fat gain, in the very long term it may not produce as much insulin resistance as one would otherwise expect. Diabetes risk is greatly elevated in the three years following smoking cessation (5), and this is likely due to the fat gain that occurs. This is not a good excuse to keep smoking, because smoking tobacco is one of the most unhealthy things you can possibly do. But it is a good reason to tighten up your diet and lifestyle after quitting.